ST/EST 404 THE EARTH & SPACE
CHAPTER 7 NOTES
CHAPTER 7
The Atmosphere
(pp. 222 – 245)
1 The Atmosphere
The atmosphere is the layer of ______that surrounds the Earth. The gases that make it up are essential for life on our planet.
How do the gases help sustain life on Earth?
• It filters out harmful dangerous rays from the sun such as ______rays.
• It maintains a stable climate on Earth by retaining ______.
• It’s made up in part by ______which is necessary for cellular respiration and by ______which is necessary for photosynthesis in plants.
99% of the Earth’s atmosphere extends just ______above the Earth’s surface
(The other 1% extends 10,000 km above the Earth’s surface!!!)
The particles that make up the atmosphere are held close to the Earth’s surface by the force of ______.
1.1 The Composition of the Atmosphere
•Most (99%) of our atmosphere is made up of ______(21%) and ______(78%).
•The rest is made up of ______and other gases.
•The air also contains solid and liquid particles that come from the Earth’s surface
(Examples: ______, pollen, soot,
______, ______, etc.)
The Earth’s atmosphere is divided into 5 main layers (p.225). There are also two important characteristics of air - ______and ______which vary with altitude. The higher the altitude, the ______the air particles in the atmosphere.
Atmospheric Pressure
· ATMOSPHERIC PRESSURE is the ______in the atmosphere.
It is caused by the pressure exerted by the ______molecules in the air when they ______with each other and the surfaces in their path.
More collisions = ______pressure
Atmospheric pressure at sea level = ______kPa (1 kPa = 100kg/m2)
QUICK CALCULATION:
If the average surface area of a human is 2 m2, what mass of air is exerting pressure on you right now? (Assume you are at sea level) ______!!!
2 Factors That Affect Atmospheric Pressure
1. The number of air particles: As the number of particles increases, the air pressure ______.
2. The air temperature: As the temperature increases, the particles in the air move farther apart which causes the density of the air to ______. As a result, warm air is ______than cold air and has a tendency to ______.
Why does atmospheric pressure depend on your location and vary over time at your location?
______
______is created when air particles move from areas of ______pressure to areas of ______pressure.
1.2 Atmospheric Circulation
· ATMOSPHERIC CIRCULATION is the global-scale movement of the layer of ______surrounding the Earth.
Warm (less ______) air from the equator moves towards the ______.
It is replaced by colder (more ______) air from the ______.
F This phenomenon is called ______.
Coriolis Effect
On a non-rotating planet, air masses would flow directly from north to south and south to north.
Because the Earth is rotating, air masses trajectories change through what is called the ______Effect.
Winds therefore deviate to the ______in the Northern Hemisphere and to the ______in the Southern Hemisphere. These movements of air occur in the ______and play an important role in meteorological phenomena. They are responsible for the formation of ______, ______and the subsequent clouds, which occurs when air masses of different properties come into contact.
PREVAILING WINDS (EST ONLY)
Winds form great loops called ______.
Each hemisphere contains three circulation cells:
1. ______cell
2. ______cell
3. ______cell
Near the surface, the atmospheric circulation cells create ______winds, which are winds that blow in characteristic directions on a global scale. Their course is determined by the ______effect.
· PREVAILING WINDS are major atmospheric currents that blow in a given ______according to ______patterns of movement.
Prevailing winds consist of:
1. Polar ______(move between the pole and the 60th parallel)
2. ______(Prevailing winds in Quebec, blow from _____ to _____)
3. ______winds (move between the 30th parallel and the ______)
· On the regional level, winds are influenced by local high and low ______systems.
· At very high altitudes, powerful winds called ______blow from west to east around the Earth between the circulation cells.
Each hemisphere has two jet streams: a sub- ______jet stream and a ______jet stream. (Cool fact: Pilots avoid these or use them to their advantage.)
F YOU MUST STUDY FIGURE 7.7 (Circulation cells and prevailing winds) ON P. 227 OF YOUR TEXTBOOK
AIR MASSES
· An air mass is a large expanse of the ______with a relatively uniform ______and ______.
The climate in Quebec is affected by six 4 different air masses: (Refer to Figure 7.10 on p. 229)
- Polar continental air mass: ______and dry
- Polar maritime air mass: ______and humid
- Tropical continental air mass: ______and ______
- Tropical maritime air mass: ______and ______
When two air masses meet, they do not mix. The colder air slides ______the warmer air. The line where the two masses meet is called a ______.
COLD FRONTS
A cold front forms when a mass of ______air advances on a mass of warm air. The warm air rises rapidly, in a sharp ascent, and then cools. The resulting condensation forms puffy clouds called ______, which often produce ______and ______rain.
WARM FRONTS
A warm front forms when a mass of ______air moves toward a mass of cold air rising gently above the cold air and creating ______clouds of many stratified layers called ______. Warm fronts often bring ______weather and ______that are ______to disappear because warm fronts do not travel as fast as cold fronts.
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ST/EST 404 THE EARTH & SPACE
CHAPTER 7 NOTES
COLD FRONT
WARM FRONT
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ST/EST 404 THE EARTH & SPACE
CHAPTER 7 NOTES
ANTICYCLONES (H) & DEPRESSIONS (L)
Ø An ANTICYCLONE is an area of atmospheric circulation surrounding a ______- pressure center. The air rotates ______in the northern hemisphere and ______in the southern hemisphere.
· The sky is ______and the weather is stable: dry & ______in the summer and ______in the winter.
· On a weather map, anticyclones are symbolized by an ______(for “high pressure”)
Ø A DEPRESSION is an area of atmospheric circulation surrounding a ______-pressure center. The air rotates ______in the northern hemisphere and ______in the southern hemisphere.
·
·
·
·
·
·
· Encourages ______formation and results in ______(rain, drizzle, sleet and snow, etc).
· On a weather map, depressions are symbolized by an ______(for “low pressure”)
Cyclones, Hurricanes and Typhoons, Oh My!
A cyclone is a violent ______storm characterized by rapid inward circulation of air masses about a ______pressure center. (In North America we call them hurricanes, in Europe they are called cyclones and in Asia they are called typhoons.)
Hurricane of the year: ______
1.3 The Greenhouse Effect
Ø The GREENHOUSE EFFECT is a natural process that allows the Earth to ______some of the ______it receives from the Sun.
Without it the average temperature of the Earth would be -18oC!!!! Brrrrr!!!
Greenhouse gases, mainly ______, ______, ______and ______, have always existed around our planet. They act like a ______trapping ______from the Sun on our planet.
THE THREE STEPS OF THE GREENHOUSE EFFECT (Refer to Figure 7.16 on p. 233 of your text)
1. Most of the ______rays that reach the Earth’s surface are ______by the ground.
2. Once heated, the ground emits ______rays into the ______. Some of the ______rays escape through the atmosphere and are ______in space.
3. Greenhouse gases ______some of the ______rays and send them back to ______, further ______its surface.
THE INTENSIFICATION OF THE GREENHOUSE EFFECT
Carbon dioxide levels have been constant for millennia. It entered the atmosphere from forest fires, volcanic eruptions, and animals (cellular respiration). And it was absorbed from the atmosphere by:
1. ______(through photosynthesis)
2. ______(dissolving and absorption by phytoplankton)
This fine balance maintained a stable temperature on Earth until the past century, when human consumption of ______fuels increased and led to enormous quantities of ______being released into the atmosphere.
F CO2 is the main product of ______of oil, natural gas and coal.
How does clearing land for farming contribute to increased CO2 levels?
______
Ø ______CHANGE is a shift in long-term average weather patterns on Earth, caused by human activities.
OTHER GREENHOUSE GASES
1. Methane (CH4) is _____ times stronger at trapping heat than CO2. It comes from:
· The digestive systems of ______animals
· Storage and management of ______
· The decomposition of household ______
· The distribution of natural gas
2. Nitrous oxide (N2O) comes primarily from:
· The spreading of ______on farmland.
· The manufacturing of certain chemicals.
Between 1850 and 2005, the average temperature of the Earth has increased by 0.76oC. An increase of just 2oC will cause serious disturbances in our climate.
Examples of such disturbances are:
· ______
· heat waves
· ______
· ______
1.4 The Contamination of the Atmosphere (EST ONLY)
Other atmospheric contaminants:
1. Sulfur dioxide (______) and nitrogen oxides (______) are responsible for ______and are a source of ______.
2. Metals such as ______(Hg), ______(As) and ______(Pb) which come mainly from oil and coal combustion. They are toxic in small amounts because they ______in living organisms.
3. ______(CFCs) destroy ______(O3) molecules.
4. ______and airborne particles
Once in the air, what happens to these contaminants? ______
THE THINNING OF THE OZONE LAYER (EST ONLY)
Ozone (______) exists as a gas in the atmosphere. It is more highly concentrated in the ______.
Ø The OZONE LAYER is a part of the ______with a high concentration of ozone molecules, which absorb some of the ______rays from the sun.
______s, compounds used in refrigeration systems and aerosol cans, were found to be responsible for destroying ozone molecules in the stratosphere.
When a CFC molecule rises up into the atmosphere it absorbs UV rays. This causes the ______atom on the CFC molecule to break off. The ______atom then bonds with an ozone molecule and turns it into oxygen (______).
SMOG (EST ONLY)
Ozone in the stratosphere is ______, but ozone at ground level (tropospheric ozone) is ______because it can cause serious ______problems.
Tropospheric ozone forms when the sun rays hit ______molecules which come mainly from car ______and ______.
Ø SMOG is a thick mixture of ______, ______and atmospheric pollutants.
Smog is formed when tropospheric ozone combines with ______or ______.
1.5 Energy Resources
What type of energy is converted from wind energy? ______
WIND ENERGY
The main advantage of wind power is that it’s a ______resource.
The disadvantages include:
1. ______the beauty of the landscape. (UGLY!)
2. Wind is ______.
3. Wind energy ______be stored.
2 The Effect of the Sun and the Moon of the Earth
The Sun and the Moon are the two celestial bodies in our Solar System that have the greatest effect on the Earth.
· The Sun provides the Earth with ______and ______.
· The Moon exerts a gravitational force, which creates ______.
2.1 Solar radiation
· The sun is a ______made up of ______and ______.
· ______reactions convert the ______into ______which produces energy.
· Solar energy from the sun is transported through space by ______waves.
· It takes ______for the energy from the Sun to travel 150 million km to the Earth.
· Although the sun emits waves from the whole electromagnetic spectrum, only ______, ______, and ______penetrate our atmosphere and reach the Earth’s surface. The rest are filtered out.
These rays heat the atmosphere, the oceans and the ground. Tropical regions receive ______heat than the Polar Regions. The resulting temperature differences produce ______(winds) and ocean ______, which circulate heat around the globe.
SOLAR ENERGY
The Earth receives enough energy from the Sun in one hour to support all of our energy needs for one year!!! The problem is harnessing that energy.
Various technologies have been designed to harness the Sun’s energy:
1. Passive heating systems
· Involves positioning houses so that they absorb the most ______and ______from the sun. (i.e. Facing ______)
· Using heat absorbing materials (i.e. ______floors)
2. Photovoltaic cells
· Used to supply certain appliances or an entire home with ______.
· When sunlight hits the silicon in the cells, it sets the ______in motion which creates an electric ______.
3. Solar Panels (collectors)
· Used to heat ______in buildings, and ______in homes or swimming pools.
· Copper ______filled with moving ______are coiled underneath large glass panels. The panels capture the ______of the sun’s rays which heats the ______in the pipes. That water is then pumped to radiators or other heating units.
Advantages and Disadvantages of Harnessing Solar Energy
ADVANTAGES / DISADVANTAGES- Can be used in remote areas that cannot connect to the main electricity grid. /
2.2 The Earth-Moon System
From the analysis of lunar rock samples collected during space expeditions, scientists put forward the theory that 4.6 billion years ago, a meteorite the size of Mars hit the Earth and blew off a large part of it scattering pieces into space. These pieces of Earth gathered together to form the Moon.
The Moon rotates around the Earth in ______days. This is also the same time it takes to do one complete rotation on its own axis. The two movements are ______.
TIDES
As the Earth rotates on its axis, the bodies of water facing the Moon are pulled toward it by the force of ______. As a result, the waters swell creating a slight bulge in the direction of the Moon.
The rise and fall of ocean waters caused by the ______force of the ______and to a lesser degree the Sun on the Earth.
· The areas on globe where the waters swell are called ______tides.
· The areas on the globe where the waters do not swell are called ______tides.
· In a 24 hour period, the Earth has _____ high tides and _____ low tides.
· The difference between the water level at high tide and at low tide is called the ______.
FCHECK OUT THIS VIDEO ON TIDES:
http://www.mmscrusaders.com/newscirocks/tides/tideanim.htm
The ______of tides varies with location and the seasons.
Tidal range is influenced by:
· The shape and ______of the coastline
· ______
· The distance of the ______and ______with respect to the Earth.
· When are the tides with the greatest possible amplitudes created?
______
· Where are the highest tides in the world reaching amplitudes of 17 meters?
______
TIDAL ENERGY
Ø TIDAL ENERGY is the energy drawn from the ______and ______of tides.
To be cost effective, the amplitude of the tide has to be at least ______meters high.
Advantages and Disadvantages of Tidal Energy
ADVANTAGES / DISADVANTAGESEND OF CHAPTER 7
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